Could somone give me a hint as to why my division by 0 check doesn't work?

```
istream & operator >> ( istream & is , Rational & r )
{
char x ;
is >> r.num >> x >> r.den ;
if ( r.den == '0' )
{
cout << "Division by '0' impossible - Exiting program" << endl ;
exit ( 1 ) ;
}
return is;
}
```

x should be the '/' symbol